The invention relates to touch-sensitive control panels, also known as touch screens, for controlling appliances.
Touch-sensitive control panels are becoming more common in domestic appliances. In addition to providing more aesthetically pleasing control interfaces, touch-sensitive control panels provide more flexibility than more conventional control panels based on mechanical switches and rotary knobs. Touch-sensitive control panels are also less prone to failure through use due to their lack of moving parts. Touch-sensitive control panels can allow for a sealed interface between a user and the inside of a domestic appliance. This prevents spilt fluid or other debris from entering a domestic appliance through the gaps which surround conventional mechanical switches and knobs. A touch-sensitive control panel additionally provides a surface which can easily be wiped clean. This makes them more hygienic that more conventional control panels as there are no crevices or joints in which dirt may accumulate.
However, a problem with touch-sensitive screens in that they can be prone to accidental activation. A conventional electric hob control might include a rotary dial which is ‘clicked-on’ from an off position to activate the hob. The rotary dial may then be further rotated to select a desired temperature for the hob. This kind of control require a specific rotary action to operate. In addition, the mechanical resistance of the control, for example the force required for it to be ‘clicked-on’, can be chosen to reduce the chance of accidental activation. This means it is unlikely that a child or a pet, for example, could activate the hob control unintentionally. A hob having a touch-sensitive control panel can more easily be activated by a child playing with the hob or a pet walking over the control panel. This can make such hobs, and other appliances having touch-sensitive control panels, potentially significant sources of danger. Furthermore, when a hob, or other appliance, with a touch-sensitive control panel is in normal use it can be relatively easy to accidentally change the appliance settings, for example the temperature of a hob, merely by brushing past the control panel when reaching across the appliance or when attempting to adjust some other function of the hob. This is undesirable since it prevents the appliance from functioning as the user intends, and how he believes it to be, operating.